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Home >> Lexus >> 2005 >> SC 430 >> Repair and Diagnosis >> Steering >> Power Steering >> Progressive Power Steering System - Diagnostics >> System Description
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System Description

  1. SYSTEM FUNCTION 
    1. Progressive Power Steering (PPS) is a vehicle speed sensing type of power steering, which increases/decreases steering support in accordance with vehicle speed.

      The power steering ECU sends a control signal to the steering gear (PPS solenoid valve) based on a vehicle speed signal. As a result, the steering feels tighter when driving at high speeds.

  2. FUNCTION OF MAIN COMPONENTS 
    MAIN COMPONENTS FUNCTION

    Item Function
    Power steering ECU assy Power steering ECU receives vehicle speed signal from combination meter. It then sends signal to PPS solenoid valve.
    PPS solenoid valve assy PPS solenoid valve controls power steering fluid pressure after receiving signal from power steering ECU.